Beiträge von LaSource

  • New engine

    Hi - Unfortunately the engine in the XBow blew up last week. Looks like a rod punched a hole in the bottom block.


    So I will be looking for a new engine for the Xbow. The car was previously running about 350hp with additional upgrades. Therefore I am looking for solutions that give 360+ hp. 400+ would be nice but it needs to be reliable for track day use so not sure if that is possible.


    What do you recommend as a starting point? I have been advised to go S3 CDL engine. Anyone tried a 5cyl TTRS engine?


    Thanks.

  • Replacement battery for XBow

    I guess I was being lazy thinking. Instead of one that lasts a week, get one that lasts longer (even though car is normally on trickle charge) for the additional 5 kgs…


    ...but maybe I blaspheme on a lightweight forum :D

  • Replacement battery for XBow

    Hi - I have a 2009 XBow (upgraded to 350hp). It currently has a lightweight battery (similar to a motorcycle battery). It recently lost charge at a track day. I am thinking of replacing it now with a tradition/normal battery.


    Does anyone have any knowledge of what size/type of battery is appropriate for the XBow?


    Also, any tips or pointers on the replacement procedure? Key in ignition, not in ignition? Find little nephew to crawl into passenger footwell? :)


    thanks.

  • Mass Air Flow sensor

    Hi - can I ask which MAF you tend to replace with nowadays? The little plastic retaining clip is broken on mine so I thought I would replace with a new MAF.


    The current one has the following markings:

    HC1 AFH60M-27

    I believe it may be a Hitachi item? Not sure if it is the original MAF or has been previously replaced. Usually I understand most people recommend Bosch items


    [Blockierte Grafik: https://i.imgur.com/shrrC25.jpg]


    Thanks.

  • Help : XBow lost boost

    Yes - broken turbo :(

    The intake impeller nut had come off and jammed into the fan blades. Could have been worse I guess


    Wimmer correctly diagnosed the issue with the turbo...and then gave me an additional nice bill for a 'smoke test' which I hadn't really asked for. Language barrier meant they were not motivated to get me back on the road same day even though I could see they had a spare turbo on the shelf (standard K04).


    But any way, car came back to UK and now fixed and back on the road.


    My adventure with slicks at Spa remained unfulfilled. Last time the gearbox broke before I could try the slicks, this time the turbo before I could get any heat in them....so operation sub 2.40 will have to wait until another time! Think from now on the XBow will only go as a spare car, I cannot trust it as the only car at a European track day. Wish I had also taken the GT3RS at Spa - was going to but backed out at the last minute.

  • Help : XBow lost boost

    Hi. I am currently at Spa.


    1st session on slicks.
    Lap 5 at Pouhon, sudden loss of power.
    Engine, gearbox, clutch all fine. But no boost. No hissing/boost leak noise.


    The guys at LLM mecasport/La Source currently looking at it but not found any loose hoses or anything.


    Is this a common problem? Any ideas?
    Will ask Wimmer next I guess.

  • Semi Slick

    You are right. I agree.
    It was one of those last minute events - booked 5 hours in advance, XBow being fixed, thought I could get a day at a new track from them.


    But yes, they were well worn - probably a bit irresponsible with hindsight.


    But I thought maybe useful for others to note.

  • Semi Slick

    It would appear the issue is at the inside edge of these tyres.


    Here is the other front tyre which did not exhibit the same catastrophic wear on the outer side of the tyre. But you can see the inner tube is beginning to degrade on this without it being apparent on the outside.


    It is a shame as I was originally a big fan of this tyre for track grip.


    These examples are from an E46 M3 where the weight of the car is at the front and hence the front inside shoulder having the issue. On the XBows I guess the rear inside shoulder is under more stress.

  • Semi Slick


    Ok - some more photos for posterity.


    Some pictures of the inside of the tyre

  • Semi Slick

    Hiller schrieb:

    Super Vergleich Stephan! Danke !
    Vorallem weiß ich du lässt es auch gut Fliegen und die Zeiten sind konstant!


    Jetzt fehlt ein Vergleich im Regen Toyo vs. Yoko



    haha - that could be a complete lap vs a picture from a grassy field :)

  • Semi Slick

    So...this week I think I was lucky to just miss a R888R failure on an M3. Although not XBow related, I thought it might be interesting to share the pictures here.


    I went to a regional track called Snetterton in a E46 M3 running well used R888R tyres. The front tyres were low on the inside edge (front is running approx 3-3.5 neg camber) but I thought it might have 1-2 track days left in it. The track is two hours away for me and since the tyres were close to legal minimum, I drove the car there and back on a different set of fronts wheels and changed to the R888R fronts at the circuit


    Had a great day, first time on this circuit - the track and car turned out to be fairly aggressive on the tyres. At the end of the day I took off the front tyres to replace with the road wheels and was shocked to see the outside front tyre had an extreme radial gash with wire mesh showing underneath. The tyre was still air tight but must have been at risk of failing at any time.


    My learning points from this were:
    - The R888R can deceptively look like there is plenty of rubber but actually you are close to the structure/wire mesh of the tyre underneath (and maybe all tyres but I think the shape of the R888R lends itself to this)
    - High neg camber cars may be more at risk where the rest of the tyre seems like there is lots of rubber left but the inner shoulder is actually very low
    - Once the inner should wears significantly the tyre structural strength is compromised. Of course on closed wheeled cars it is important to keep an eye on the inner shoulder as you can't see it easily.


    Anyway, not sure if the above is R888R specific or a problem for any high wear tyre. Pics attached.

  • Semi Slick

    matthias schrieb:

    Just also going to try the Yokohama, 225 front and 265 rear. Thanks for your advices!


    For the German buyers... there is a 10% coupon (PSOMMER17) valid for summer tyres on eBay - it ends today. :biggrin:


    Out of interest, are the sizes you quote above common alternative sizes for the XBow? What is the main driver - wider rubber on the road or price/availability?


    Gripgroove schrieb:

    Hallo Stephan,


    vielen Dank für diesen Vergleich! :Daumen hoch:
    Es scheint ja demnach so, dass der Performance-Unterschied der beiden Reifen deutlich kleiner ist als der Preis-Unterschied... :denk:


    LG
    Christoph


    +1 my conclusion too